Slide fasteners



April 5 w. MIKULAS 2,705,356

sum: FASTENERS- Filed July 5, 1952 IN VEN'TOR. .WILUAM MIKULAS ATTQRNEYS United States Patent 2,705,356 SLIDE FASTENERS William Mikulas, Staten Island, N. Y., assignor to Conmar Products Corporation, Newark, N. J., a corporation of New Jersey Application July 3, 1952, Serial No. 297,093 10 Claims. (Cl. 24-205.14)

The invention relates to an automatic lock slider for slide fasteners of the type comprising a pair of stringers provided with spaced, interlockable fastener elements.

More specifically, the present invention relates to an improved automatic lock slider of the type having only three elements; namely, a slider body, a locking member having an integral spring portion and a pull device. Sliders of this type are generally shown in the patents to Disinger and Ulrich, 2,521,453, granted September 5, 1950 and Ulrich and Disinger, 2,523,740, granted September 26, 1950.

The primary object of the present invention is to simplify and improve the construction of automatlc lock sliders of the three element type.

A further object of the invention is to provide the locking member with integral spring means affording a strong, positive locking action to thereby improve the quality of the resultant product.

Still a further object of the invention is to so form the locking member that it will provide simplified means for connecting the locking member to the slider body so that the locking member will withstand the application of excessive force to pull it away from the slider body, such means, in the preferred form of the invention, serving to additionally protect the locking member against the abuse it will encounter in usage.

Still another object of the invention is to so construct the slider body and locking member elements that the assembly of the parts is greatly simplified with the attendant decrease in the cost of manufacture of the prodnot.

To the accomplishment'of these objects, and such other objects as may hereinafter appear, the invention is directed to an automatic lock slider and the component combinations thereof, as sought to be defined in the appended claims and as described in the following specification, taken together with the accompanying drawings, in which:

Fig. 1 is a side elevational view of an automatic lock slider made in accordance with the present invention with the locking member in locked position;

Fig. 2 is a top view of the automatic lock slider shown in Fig. 1;

Fig. 3 is a simplified end view looking towards the left of the automatic lock slider shown in Fig. 1;

Fig. 4 is a perspective view of the locking member prior to its assembly with the slider body;

Fig. 5 is a View similar to Fig. 1 showing the locking member in its unlocked position; and

Fig. 6 is a fragmentary cross section taken approximately in the planes of lines 66 of Fig. 2, the locking member in this view being in unlocked position.

Referring now more in detail to the drawings, and more particularly to Figs. 1 to 3, the automatic lock slider of the present invention comprises only three pieces or elements, a slider body S, a locking member L and a pull device P. The slider body S comprises a rear wing 10 and a front wing 12 connected together at their upper ends by a substantially diamond-shaped neck or post 14. The rear wing 10 comprises a body wall provided with inturned opposite flanges 16, 16', and similarly, the front wing 12 comprises a body wall provided with inturned opposite flanges 18, 18'. The described construction defines an interior Y-shaped slider channel C for the fastener elements 1 of the slide fastener stringers. The pull device P is of the common variety, and comprises a finger-grasping portion 20, a pair of arms 22, 22', having inturned trunnions 24, 24 at their ends.

The locking member L is mounted on either one of the wings of the slider body S, and in the form of the invention shown, the locking member is mounted on the 2,705,356 Patented Apr. 5, 1955 front wing 12. The front wing 12 is provided with a substantially rectangular window 26 opening into the slider channel C, the long dimension of the window extending parallel to the longitudinal axis of the slider body. Immediately adjacent and on each side of the window 26 near the lower end thereof, the front wing 12 is provided with inclined or cam surfaces 28, 28' for a purpose to be subsequently described. The cam surfaces 28, 28' converge in a direction toward the top surface of the front wing. The medial upper wall portion 30 at the top end of the window 26 defines a mounting seat or fulcrum for pivoting the locking member L. The wall portion 30 also provides engaging parts to prevent disengagement of the locking member from the slider body. Preferably, and as best. shown in Fig. 1, the wall portion 30 is pressed out so as 'to be elevated slightly above the wall of the front wing 12.

As best shown in Fig. 4, the locking member L includes laterally spaced portions 32, 32' which are designed to extend substantially parallel to the longitudinal axis of the slider body S. More specifically, the portions 32, 32 comprise a pair of substantially upright side walls which, preferably, are resiliently connected together by an integral arcuate-shaped portion 34 at their top ends. The side walls 32, 32 and the connecting portion 34 are substantially in the form of a U, with the side walls constituting the arms and the portion 34 the base. The unitary locking member is formed by stamping and bending a strip of material. having spring characteristics, such as spring steel or a suitable alloy of beryllium-copper.

The side walls 32, 32' are provided with apertures 36, 36 formed so that their upper surfaces will provide camming faces 38, 38' for engagement by the trunnions 24, 24' of the pull device P. The side walls are provided at their free or rear ends with detents 40, 40' for engagement with the fastener elements f. Immediately adjacent and above each detent, the side walls are formed to provide cam surfaces 42, 42. These cam surfaces, and detents, are formed by bending the side walls outwardly at these areas so that the cam surfaces each possess approximately the same complementary angle as the cam surfaces 28, 28 on the slider body with which they are to cooperatingly engage.

To prevent the locking member from being disconnected from, or pulled off, the slider body, means are provided for connecting them together, while allowing relative movement between the two elements. The top end of the locking member L is provided with stop elements 44 formed as projections on the top end of each side wall and beneath the connecting portion 34. The stop elements 44 together with the connecting portion 34 provide notches 46. Means for completing the assembly of the locking member and slider body may be provided in accordance with the construction described in the patent to Ulrich et al. 2,523,740, granted September 26, 1950, wherein a flange is formed on the slider body at the lower end of the orifice or window and is bent down over stop elements provided at the rear end of the locking member. In accordance with the present invention, however, means are provided for simplifying the assembly of the locking member with the slider body. Also, the improved means for connecting the locking member with the slider body preferably is formed to provide protection for the locking member itself against any abuse to which it may be subjected in use.

Preferably, this is accomplished by providing the locking member with a cover plate 48, formed as an integral part of the locking member. The cover plate 48 extends from the portion 34 connecting the side walls back over the top edges 50, 50 of the side walls. The cover plate 48 is formed with a downwardly bent portion 52 which terminates in a centrally located or intermediate stop prong 54. Except for the prong 54 which is of reduced width, the cover plate 48, as shown in Fig. 3, is of a width substantially equal to, or only slightly greater than, the distance between the extreme outer edges 56, 56' of the side Walls 32, 32' in the finally assembled slider, as best shown in Fig. 3. The side walls are each provided at their rear ends with stop spurs 58, 58' for engagement with the prong stop 54.

If desired, the intermediate prong stop 54 may be formed as a projection on the medial portion of the slider body immediately below the window 26 and between the side walls 32, 32', instead of being formed as a part of the locking member. The stop spurs 58, 58' would cooperate with such stop in the same manner as will be hereinafter described.

To assemble the three described parts of the automatic lock slider, the locking member L first is assembled with the slider body S. This is accomplished by pressing the side walls 32, 32 together against the spring action exerted by the connecting portion 34 until their rear ends at the stop spurs 58, 58' touch, or nearly touch each other. The outwardly extending detents 40, 40 will now clear the longitudinal edges of the window 26 so that the locking member may be inserted in the window 26. The notch 46 is slipped over the medial portion 30 of the slider body and the spurs 58, 58' are simply brought down on the medial part of the slider wing 12 immediately below the. window 26. The pressure on the side walls 32, 32 is then released causing them to spring apart into substantial parallelism, whereupon the cam faces 42, 42' of the locking member will bear against the corresponding cam faces 28, 28 on the slider body, the spring action tending to spread the side walls apart causing the locking member cams to assume their lowermost position on the slider body cams. At this point, the detents 40, 40' are located in the slider channel C in the path of the fastener elements 1 of slide fastener stringers, and the upper end of the locking member L is prevented from being lifted away from the slider body by the steps 44 engaging the lower surface of the medial portion 24.

To complete the assembly and connect the bottom end of the locking member to the slider body, the cover plate 48 is bent down until its under surface substantially abuts the upperedges 50, 50' of the side walls and the stop prong 54 is disposed between the stop spurs 58, 58'. The bottom edges of the downwardly bent portion 52 adjacent the prong stop 54 sit on top of the stop spurs 58, 58'. The width of the prong stop 54 is selected to permit the side walls 32, 32 to move towards each other only an amount which will allow the detents 40, 40' to move towards each other and upwardly just enough to clear the lower surface of the top wing 12, as shown in Fig. 6, when the stop spurs 58, 58 will press against opposite sides of the prong stop 54 and prevent any further upward movement of the locking member. The locking member is now securely anchored to the slider body to prevent its removal therefrom while mounted to permit the necessary relative movement. When so assembled, the locking member L assumes the position shown in Figs. 1 and 3, the top of the mounting wall portion 30 providing a fulcrum F for engagement by the front edge of the side wall connecting portion 34, and the rear edge of the mounting wall portion where it meets the window 26 providing a second fulcrum F for the locking member L at the top of the notches 46. Finally, the pull device P is assembled with the slider body and locking member by bending the arms 22, 22 inwardly and into parallelism so that the trunnions 24, 24' are received within the apertures 36, 36 of the side walls.

In operation, and as shown in Figs. 1 and 3, the locking member is automatically maintained in locking position with the detents 40, 40' disposed in the slider channel C for engagement with fastener elements 1. This position is normally maintained by the locking member, because of the spring action upon the side walls 32, 32 tending to spread them apart, thereby causing the cam surfaces 42, 42 to be maintained at their lowest positions on the cam surfaces 28,28. When cross-pull is applied to the fastener above the slider tending to open the fastener, the slider tends to move downwardly relative to the stringers thereby bringing the detents 40, 40', if they are not yet in engagement with the fastener elements f, into locking engagement with the elements 1. The thrust exerted by the fastener elements upon the locking member is taken up by the portion of the locking member L where the top of the notches 46 engage the fulcrum F whereby the continued pressure of the fastener elements f against the detents 40, 40' causes the locking member L to tend to rock inwardly about this fulcrum F with the result that the locking member is forced all the more into locking position. The stops 44 engage the underside of the medial portion 30 if any excessive force is applied tending to lift the locking member away from the slider body.

The slider is unlocked in the usual way by either a downward pull, during the opening of the slide fastener, or an upward pull, during the closing of the slide fastener, exerted on the pull device P. During a downward pull thereof, the pull device is moved from the position shown in Fig. 1 to that shown in Fig. 5, during which movement the trunnions 24, 24 engage the cam surfaces 38, 38', thus forcing the locking member L to be lifted against the resilient or spring action exerted upon the side walls 32, 32. In moving upwardly, the locking member L pivots about the fulcrum F. The inclination of the cooperating cams is such that the cams 42, 42 will ride up on the cams 28, 28', thereby causing the side walls 32, 32' to be compressed towards each other until the detents 40, 40 clear the bottom face of the slider wing 12 and allow free movement of the slider. The detents, like the side walls, move towards each other and upwardly during the unlocking action. The parts are so dimensioned that the locking member cannot be rocked any further about the fulcrum F when the detents clear the slider channel, because the stop spurs 58, 58' will press against opposite sides of the prong stop 54 to prevent any further upward movement of the locking member. At this stage the relationship of the parts is as shown in Fig. 6. Portions of the cams 42, 42 are still in engagement with portions of the slider body cams 28, 28' to additionally provide obstructions against further and unnecessary movement of the locking member away from the slider body. When the force on the pull device is released, the side walls 32, 32 tend to spread apart whereby the cam surfaces 42, 42 will ride downwardly on the corresponding cam surfaces 28, 28, thereby returning the detents 40, 40 into the slider channel for engagement with fastener elements 1. Thus, when unlocking, or when the locking member is returning to locked position from unlocked position, the resiliently connected side walls 32, 32 move laterally with reference to each other. When it is desired to move the slider in the opposite or fastener-closing direction, the detents 40, 40 will freely ratchet over the fastener elements 1, as is common in most types of automatic lock sliders. Upon release of the pull device P after either a downward or upward pulling operation, the locking member L automatically returns to its locking position, as shown in Figs. 1 and 3.

In the construction thus provided, it will be apparent that the product possesses novel and highly improved functions and characteristics. While the preferred form of the automatic lock slider has been shown and described, it will be apparent that changes may be made therein without departing from the spirit of the invention as defined in the following claims.

I claim:

1. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said locking member including laterally spaced side walls disposed within said window and resiliently connected together by a part which acts against said fulcrum, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement, under the action of said resiliently connected side walls, of the slider body and locking member cam surfaces serving to maintain the locking member in looking position, and the application of a force to the pull device against the locking member causing said locking member to move about said fulcrum and said resiliently connected side walls to be moved laterally with reference to each other and move the locking member to unlocking position.

2. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said cam surfaces converging in a direction towards the top surface of the front wing, said locking member comprising a pair of laterally spaced side walls disposed within said window and resiliently connected together by a part which sets against said fulcrum, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement, under the action of said resiliently connected side walls, of the slider body and locking member cam surfaces serving to maintain the locking member in locking position, and the application of a force to the pull device against the locking member causing said locking member to move about said fulcrum and said resiliently connected side walls to be compressed towards each other and move the locking member to unlocking position.

3. An automatic lock slider for slidefasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said locking member comprising a pair of laterally spaced side walls disposed within said window and resiliently connected together at their top ends by an integral connecting portion, said connecting portion engaging the fulcrum for unlocking the locking member provided by said front wing, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a camming aperture in each side wall to receive a part of said pull device, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement, under the resilient action of said connecting portion, of the slider body and locking member cam surfaces serving to maintain the locking member in locking position, and the application of a force to the pull device against the camming apertures of said side walls causing said resiliently connected side walls to be moved laterally with reference to each other and move the locking member to unlocking position.

4. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking mem ber, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said locking member comprising a pair of laterally spaced side walls disposed within said window and resiliently connected together by a part which acts against said fulcrum, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a camming aperture in each side wall to receive a part of said pull device, an intermediate stop located between said side walls near the lower end of the locking member, a stop provided at the lower end of each side wall for engagement with opposite sides of said intermediate stop, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement, under the action of said resiliently connected side walls, of the slider body and locking member cam surfaces serving to maintain the locking member in locking position, and the application of a force to the pull device against the camming apertures of said side walls causing said locking member to move about said fulcrum and said resiliently connected side walls to be compressed towards each other and move the locking member to unlocking position, the engagement of the aforesaid stops limiting the amount the side walls are compressed and the position of the locking member in its unlocking position.

5. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for engaging said locking member,

said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said cam surfaces converging in a direction towards the top surface of the front wing, said locking member comprising a pair of laterally spaced side walls disposed Within said window and resiliently connected together at their top ends by an integral connecting portion, said connecting portion engaging the fulcrum for unlocking the locking member provided by said front wing, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a camming aperture in each side wall to receive a part of said pull device, an intermediate stop located between said side walls near the lower end of the locking member, a stop provided at the lower end of each side wall for engagement with opposite sides of said intermediate stop, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement of the slider body and locking member cam surfaces serving to maintain the locking memberin locking position, and the application of a force to the pull device against the camming apertures of said side walls causing said side walls to be compressed towards each other and move the locking member to unlocking position, the engagement of the aforesaid stops limiting the amount the side walls are compressed and the position of the locking member in its unlocking position.

6. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said cam surfaces converging in a direction towards the top surface of the front wing, said locking member comprising a pair of laterally spaced side walls disposed within said window and resiliently connected together at their top ends by an integral connecting portion, said connecting portion engaging the fulcrum for unlocking the locking member provided by said front wing, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a camming aperture in each side wall to receive a part of said pull device, a stop provided on the top end of each side wall beneath said connecting portion, said stops and connecting portion providing notches receiving a portion of the front wing therein, an intermediate stop located between said side walls near the lower end of the locking member, a stop provided at the lower end of each side wall for engagement with opposite sides of said intermediate stop, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement of the slider body and locking member cam surfaces serving to maintain the locking member in looking position, and the application of a force to the pull device against the camming apertures of said side walls causing said side walls to be compressed towards each other and move the locking member to unlocking position, the engagement of the stops cooperating with said intermediate stop limiting the amount the side walls are compressed and the position of the locking member in its unlocking position.

7. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said locking member comprising a pair of laterally spaced side walls disposed within said window and resiliently connected together by a part which acts against said fulcrum, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, a cover for said side walls formed integrally with said locking member, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement, under the action of said resiliently connected side walls, of the slider body and locking member cam surfaces serving to maintain the locking member in locking position, and the application of a force to the pull device against the locking member causing said locking member to move about said fulcrum and said resiliently connected side walls to be moved laterally with reference to each other and move the locking member to unlocking position.

8. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said cam surfaces converging in a direction towards the top surface of the front wing, said locking member comprising a pair of laterally side walls disposed within said window and resiliently connected together at their top ends by an intergral connecting portion, said connecting portion engaging the fulcrum for unlocking the locking member provided by said front wing, said side Walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, a cover plate formed integrally with said connecting portion and extending back over said side walls, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a camming aperture in each side wall to receive a part of said pull device, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement, under the resilient action of said connecting portion, of the slider body and locking member cam surfaces serving to maintain the locking member in locking position, and the application of a force to the pull device against the camming apertures of said side walls causing said resiliently connected side walls to be compressed towards each other and move the locking member to unlocking position.

9. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said cam surfaces converging in a direction towards the top surface of the front wing, said locking member comprising a pair of laterally spaced side walls disposed within said window and resiliently connected together at their top ends by an integral connecting portion, said connecting portion engaging the fulcrum for unlocking the locking member provided by said front wing, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, a cover plate formed integrally with said connecting portion and extending back over said side walls, said cover plate terminating in an intermediate stop located between said side walls, a stop provided at the lower end of each side wall for engagement with opposite sides of said intermediate stop, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a camming aperture in each side wall to receive a part of said pull device, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement, under the resilient action of said connecting portion, of the slider body and locking member cam surfaces serving to maintain the locking member in locking position, and the application of a force to the pull device against the camming apertures of said side walls causing said resiliently connected side walls to be compressed towards each other and move the locking member to unlocking position, the engagement of the aforesaid stops limiting the amount the side walls are compressed and the position of the locking member in its unlocked position.

10. An automatic lock slider for slide fasteners of the type comprising a pair of stringers having spaced, interlockable fastener elements, said slider comprising a slider body having front and rear wings spaced to provide a channel for the fastener elements, a locking member mounted on the front wing of said slider body, said front wing providing a fulcrum for unlocking the locking member, and a pull device for said locking member, said front wing being formed with a window opening into said slider channel and a pair of cam surfaces one on each side of said window, said cam surfaces converging in a direction towards the top surface of the front wing, said locking member comprising a pair of laterally spaced side walls disposed within said window and resiliently connected together at their top ends by an integral connecting portion, said connecting portion engaging the fulcrum for unlocking the locking member provided by said front wing, said side walls extending substantially the full length of the locking member and substantially parallel to the longitudinal axis of the slider body, a stop provided on the top end of each side wall beneath said connecting portion, said stops and connecting portion receiving a portion of the front wing therebetween, a cover plate formed integrally with said connecting portion and extending back over said side walls, said cover plate terminating in an intermediate stop located between said side walls, a stop provided at the lower end of each side Wall for engagement with opposite sides of said intermediate stop, at least one of said side walls being provided with a detent for engagement with slide fastener elements in said channel, a camming aperture formed in each side wall to receive a part of the pull device, a cam surface formed on each of said side walls for cooperating engagement with the cam surfaces on said front wing, the normal engagement of said slider body and locking member cam surfaces serving to maintain the locking member in locking position, and the application of a force to the pull device against the camming apertures of said side walls causing the side walls to be compressed towards each other and move the locking member to unlocking position, the engagement of the stops cooperating with said intermediate stop limiting the amount the side walls are compressed and the position of the locking member in its unlocking position.

References Cited in the file of this patent UNITED STATES PATENTS 2,521,453 Disinger Sept. 5, 1950 2,523,740 Ulrich Sept. 26, 1950 2,568,663 Schaafi Sept. 18, 1951 FOREIGN PATENTS 638,646 Germany of 1936 

